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China Communications 2022年第4期19卷 274-290页

作者： tongyu zhao Yaqiong Liu Guochu Shou Xinwei Yao School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing 100876China School of Computer Science and Technology Zhejiang University of TechnologyChina

In recent years, artificial intelligence and automotive industry have developed rapidly, and autonomous driving has gradually become the focus of the industry. In road networks, the problem of proximity detection refers to detecting whether two moving objects are close to each other or not in real time. However, the battery life and computing capability of mobile devices are limited in the actual scene,which results in high latency and energy consumption. Therefore, it is a tough problem to determine the proximity relationship between mobile users with low latency and energy consumption. In this article, we aim at finding a tradeoff between latency and energy consumption. We formalize the computation offloading problem base on mobile edge computing(MEC)into a constrained multiobjective optimization problem(CMOP) and utilize NSGA-II to solve it. The simulation results demonstrate that NSGA-II can find the Pareto set, which reduces the latency and energy consumption effectively. In addition, a large number of solutions provided by the Pareto set give us more choices of the offloading decision according to the actual situation.

关键词： proximity detection mobile edge computing road networks constrained multiobjective optimization

Restraining effect of nitrogen on coal oxidation in different stages:Non-isothermal TG-DSC and EPR research

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International Journal of Mining Science and Technology 2020年第3期30卷 387-395页

作者： tongyu zhao Shengqiang Yang Xincheng Hu Wanxin Song Jiawen Cai Qin Xu State Key Laboratory of Coal Resources and Safety Mining China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China Department of Civil&Environmental Engineering University of AlbertaEdmonton T6G 2W2Canada

Nitrogen is widely used to prevent the spontaneous combustion of coal in underground coal mines. A spontaneous combustion-prone coal seam was studied to investigate the restraining effect of nitrogen on coal oxidation in different oxidation stages, based on non-isothermal thermogravimetry-differential scanning calorimetry(TG-DSC) and electron paramagnetic resonance(EPR) experiments. We found that the key feature temperatures grow steadily with increasing nitrogen in the oxidation environment,resulting in longer oxidation stages. The most significant finding is that there is a stagnation of the inhibitory effect of nitrogen on coal oxidation in the range of 85.0–95.0% nitrogen in the slow and the rapid oxidation stages, owing to the competitive adsorption of coal by nitrogen and oxygen. However, the restraining effect cannot be reflected by the kinetic parameters of the coal before it reaches the thermal decomposition and combustion stage. Nitrogen can also affect free radical types and free radical concentrations during coal oxidation: the higher the concentration of nitrogen in the oxidation environment, the greater the number of free radical types and the lower the free radical concentration. This experimental study improves the understanding of the restraining effect of nitrogen on coal oxidation in different oxidation stages and provides an important reference for coal fire prevention in spontaneous combustionprone coal seams.

关键词： Reaction heat Non-isothermal TG-DSC Activation energy Pre-exponential factor Free radical

A high-surface-area silicoaluminophosphate material rich in Brnsted acid sites as a matrix in catalytic cracking

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Journal of Natural Gas Chemistry 2012年第6期21卷 685-693页

作者： Shaoiun Xu Qiang Zhang zhaoxuan Feng Xiaojing Meng tongyu zhao Chunyi Li Chaohe Yang Honghong Shan State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266555ShandongChina School of Chemical Science and Engineering KTH Royal Institute of TechnologySE 10044StockholmSweden Mork Family Department of Chemical Engineering and Materials Science University of Southern CaliforniaCA 90089Los AngelesUSA

A transparent gel-like mesoporous silicoaluminophosphate material （SAP） with molar ratio of Si/Al = 20 was synthesized by hydrothermal method. The physicochemical features of SAP were characterized by XRD, XRF, BET, SEM and FT-IR spectroscopy of pyridine adsorption techniques. The results indicated that incorporation of phosphorus （P） into aluminasilica system altered the basic textural characteristics of aluminasilica. Especially after hydrothermal treatment, the material with large special surface area （up to 492 m2/g） exhibited a good performance on hydrothermal stability. Moreover, the phosphorus modifier can not only increase the amount of Br／＂{o}nsted acidic sites （up to 48.44 μmol/g） and the percentage of weak acidic sites in total acidic sites, but also regulate the acid type, such as the ratio of B/L （Lewis acid/Br？nsted acid） increased to 1.15. The performances of samples as matrices for the catalytic cracking of heavy VGO were investigated. At 520 ℃, the catalysts showed much higher gasoline and diesel oil yields achieving to 45.59 wt% and 19.20 wt%, respectively, and lower coke selectivity （2.86%） than conventional FCC matrices, such as kaolin and amorphous silica-alumina.

关键词： silicoaluminophosphate hydrothermal stability Br nsted acid sites mesoporous hydrothermal synthesis

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短波宽带波形NVIS通信链路评估

舰船电子工程 2024年第4期44卷 57-60页

作者：王鹏赵彤宇陈晓天广州海格通信集团股份有限公司广州510663

短波宽带波形通过匹配近垂直入射天馈(NVIS)系统,可实现舰船、岸船通信的高速数据交互传输,极大提升短波通信在军事和应急通信系统中的作用。首先阐述国外典型的五种短波宽带波形的技术进展,然后分析宽带波形NVIS的可行性,利用ITU模型... 详细信息

短波宽带波形通过匹配近垂直入射天馈(NVIS)系统,可实现舰船、岸船通信的高速数据交互传输,极大提升短波通信在军事和应急通信系统中的作用。首先阐述国外典型的五种短波宽带波形的技术进展,然后分析宽带波形NVIS的可行性,利用ITU模型对不同数据速率和带宽对应信噪比下的链路评估,并进行了NVIS天波测试验证,为我国短波宽带波形在舰船、岸船使用NVIS宽带通信的实现提供评估方法和依据。

关键词：短波通信 NVIS 宽带通信链路评估

Traffic Signal Control with Deep Reinforcement learning

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Traffic Signal Control with Deep Reinforcement learning

Late-stage modification of bioactive compounds:Improving druggability through efficient molecular editing

作者： tongyu zhao Peng Wang Songjinag Li Institute of computer science and technology Changchun University of Science and Technology

To decrease the impact of Partially Observable MDP on deep reinforcement learning performance of intersection signal control, A deep reinforcement learning is proposed in this paper with utilizing the real-time GPS data as well as learning the control of the traffic lights in single intersection. We integrate deep reinforcement learning network（DRQN） with recurrent neural network（RNN） and apply deep network, experience pool and greedy strategy in deep reinforcement learning strategy. It solves the problem of overestimation of target Q value and insufficient long-term experience learning in the standard reinforcement learning of traffic signal control. The comparison of performance was made between the proposed method and standard Deep Q-Network（DQN） on the partial observation of traffic situations. The experimental results show that both DQN and DRQN methods can adjust their traffic signal timing control strategies according to the specific traffic conditions as well as calculating a lower average delay time of vehicle than that of fixed-time control. Besides, the simulation effect of DRQN learning method is better than that of DQN learning method in different probe vehicle proportion environment.

关键词： Deep Reinforcement Learning Traffic signal control Partially Observable MDP Vehicle network

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1030-1076页

作者： tongyu Huo Xinyi zhao Zengrui Cheng Jialiang Wei Minghui Zhu Xiaodong Dou Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Changping Laboratory Beijing 102206China Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal UniversityShanghai 200062China

Synthetic chemistry plays an indispensable role in drug discovery,contributing to hit compounds identification,lead compounds optimization,candidate drugs preparation,and so on.As Nobel Prize laureate James Black emphasized,“the most fruitful basis for the discovery of a new drug is to start with an old drug”1.Late-stage modification or functionalization of drugs,natural products and bioactive compounds have garnered significant interest due to its ability to introduce diverse elements into bioactive compounds promptly.Such modifications alter the chemical space and physiochemical properties of these compounds,ultimately influencing their potency and druggability.To enrich a toolbox of chemical modification methods for drug discovery,this review focuses on the incorporation of halogen,oxygen,and nitrogen—the ubiquitous elements in pharmacophore components of the marketed drugs—through late-stage modification in recent two decades,and discusses the state and challenges faced in these fields.We also emphasize that increasing cooperation between chemists and pharmacists may be conducive to the rapid discovery of new activities of the functionalized molecules.Ultimately,we hope this review would serve as a valuable resource,facilitating the application of late-stage modification in the construction of novel molecules and inspiring innovative concepts for designing and building new drugs.

关键词： Late-stage modification Drug space Halogenation Oxygenation Nitrogenation Synthetic chemistry

Study on Cell Error Rate of a Satellite ATM System Based on CDMA

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Journal of Systems Engineering and Electronics 2003年第1期14卷 1-5页

作者： zhao tongyu & Zhang Naitong Communication Research Center, Harbin Institute of Technology, Harbin 150001, P. R. China Communication Research Center Harbin Institute of Technology Harbin 150001 P. R. China

Abstract: In this paper, the cell error rete (CER) of a CDMA-based satellite ATM system is analyzed. Two fadingmodels, i. e. the partial fading model and the total fading model are presented according to multi-path propagation fadingand shadow effect. Based on the total shadow model, the relation of CER vs. the number of subscribers at variouselevations under 2D-RAKE receiving and non-diversity receiving is got. The impact on cell error rate with pseudo noise(PN) code length is also considered. The result that the maximum likelihood combination of multi-path signal would notimprove the system performance when multiple access interference (MAI) is small, on the contrary the performance maybe even worse is abtained.

关键词： Satellite ATM CDMA RAKE receiver.

Brilliant Like Stars:Silk Road

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China & The World Cultural Exchange 2022年第6期88卷 F0003-F0003页

作者： zhao tongyu 不详

Size effect on light propagation modulation near band edges in one-dimensional periodic structures

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Chinese Physics B 2023年第5期32卷 421-424页

作者：唐洋王佳俊赵星棋李同宇石磊 State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China

Periodic photonic structures can provide rich modulation in propagation of light due to well-defined band structures.Especially near band edges,light localization and the effect of near-zero refractive index have attracted wide attention.However,the practically fabricated structures can only have finite size,i.e.,limited numbers of periods,leading to changes of the light propagation modulation compared with infinite structures.Here,we study the size effect on light localization and near-zero refractive-index propagation near band edges in one-dimensional periodic structures.Near edges of the band gap,as the structure's size shrinks,the broadening of the band gap and the weakening of the light localization are discovered.When the size is small,an added layer on the surface will perform large modulation in the group velocity.Near the degenerate point with Dirac-like dispersion,the zero-refractive-index effects like the zero-phase difference and near-unity transmittance retain as the size changes,while absolute group velocity fluctuates when the size shrinks.

关键词： one-dimensional(1D)photonic crystal finite-size effect band gap light localization zerorefractive-index effect

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硬泡聚氨酯喷涂内保温冷库外墙隔汽需求计算

冷藏技术 2023年第2期46卷 4-10页

作者：赵彤宇华商国际工程有限公司北京100069

采用美国材料试验协会隔汽标准的计算方法对硬泡聚氨酯喷涂内保温冷库外墙隔汽需求进行了计算与分析。提出应根据冷库冷间的设计温度、所在气候分区及外墙基层材料,计算确定是否需要设置隔汽层,以及当需要设置隔汽层时,隔汽层所需的蒸... 详细信息

采用美国材料试验协会隔汽标准的计算方法对硬泡聚氨酯喷涂内保温冷库外墙隔汽需求进行了计算与分析。提出应根据冷库冷间的设计温度、所在气候分区及外墙基层材料,计算确定是否需要设置隔汽层,以及当需要设置隔汽层时,隔汽层所需的蒸汽渗透阻,并给出了不同气候分区特定工况下隔汽层蒸汽渗透阻的建议值。

关键词：冷库外墙内保温聚氨酯隔汽层